xpBulletConstraints menu settings.
Drag the dynamic objects, that you want to constrain, into this list.
Doing so will open up parameter settings, below, which can be set separately for each individual object in the list.
In this animation, a Cylinder and a Cube (as the child) are dropped into the Objects field and the Constraint Type of Slider is selected. An Angular Min of -140 degrees and an Angular Max of 140 degrees are set, setting up a pendulum, with the Cube swinging from the Cylinder between those two degree values.
Set as Fixed, by default, these are the different constraint type options.
The alternative modes are: 6 Degrees of Freedom, Cone, Hinge, Point to Point, Slider, Spring and Sticky.
Some modes have additional parameter settings (described below).